Conventionally, in hybrid automobiles or electric automobiles, a wire harness arranged between a battery and an inverter, between an inverter and a motor, or the like includes high-voltage electrical wires that generate noise. Thus, there are cases in which the wire harness is arranged in an underfloor region below a floor panel, and, in the underfloor region, the wire harness is inserted through a metal pipe in order to protect the wire harness and to provide a shield from the high-voltage electrical wires.
For example, according to a cable holding structure provided by JP 2004-224156A, a wire harness including three-phase high-voltage cables that connect an inverter mounted on the rear side of an automobile and a motor mounted in an engine room is arranged under a floor. In the underfloor region, the high-voltage cables are one by one inserted through a protective pipe made of metal.
Furthermore, according to a shielding conductive path provided by JP 2011-146228A, as shown in FIG. 12, a metal pipe 100 is provided unitarily with a partition member 102 that projects from the inner face of a circumferential wall 101, and electrical wires 105 forming a wire harness are separately inserted through a plurality of insertion spaces 103 that are partitioned by the partition member 102. That is to say, the electrical wires 105 are separately inserted through the insertion spaces 103 as power-supply electrical wires 105A that are high-voltage electrical wires, and low current-based electrical wires 105B, so that the influence of electromagnetic noise generated by the power-supply electrical wires 105A, on the low current-based electrical wires 105B, is reduced and prevented.
If a wire harness including a plurality of electrical wires is inserted through one metal pipe 100 as disclosed in JP 2011-146228A, the number of metal pipes 100 necessary is only one. Thus, this configuration is advantageous in that the weight can be reduced and the cost can be lowered. This metal pipe is produced by extrusion molding of molten metal. According to embodiments of the present application, the metal pipe provided with the partition member is also produced by extrusion molding such that the circumferential wall and the partition member are unitarily formed.
The metal pipe may be such that the circumferential wall has a wall thickness larger than that of the partition member to increase the protective function, and that the partition member has a small wall thickness to increase the volume of the partitioned insertion spaces. However, it is not easy to partially change the wall thickness in extrusion molding of molten metal, and, thus, a sufficient level of precision may not be realized. Furthermore, it is difficult to make the wall thickness of the partition member very small. Moreover, extrusion dies for production have to be newly prepared, for example, when changing the wall thickness of the partition member while maintaining the same outer diameter of the metal pipe, when changing the shape of the partition member, or, conversely, when changing the wall thickness of the circumferential wall while maintaining the same partition member, and, thus, the production cost may increase.
Furthermore, although the configuration in which a partition member is provided is advantageous in that the influence of noise between electrical wires inserted through one metal pipe can be reduced and prevented, the providing a partition member without changing the outer diameter may reduce the volume of the insertion spaces, thereby making it difficult to insert the electrical wires therethrough, and causing contact of the electrical wire coating layer with the partition member or the circumferential wall at the time of insertion and damaging these portions.